Image forming device

Abstract

In an image forming device, a paper feed cassette accommodating a plurality of papers is removably inserted in a cassette accommodating portion of a device main body. A locking member and a lock releasing member maintain a flapper at a prescribed pressed-down position. When the paper feed cassette is inserted into the cassette accommodating portion, after the flapper at the prescribed pressed-down position is unlocked, the flapper is temporarily caught at a position within a vertical swinging range of the flapper. After the paper feed cassette is completely inserted, the flapper is released.

1. An image forming device comprising:
 a paper feed cassette which accommodates a plurality of papers; 
 a cassette accommodating portion which removably accommodates the paper feed cassette; 
 a flapper which is arranged in the paper feed cassette and swings vertically; 
 an elastic urging member which is arranged in the paper feed cassette and urges the flapper upward; 
 means for locking the flapper at a prescribed pressed-down first position when the flapper is pressed down against an urging force of the elastic urging member; 
 means for releasing the means for locking when the paper feed cassette is inserted in the cassette accommodating portion; and 
 a temporary catching portion which is formed on the means for locking and stops the flapper at a second position elevated higher than the first position when inserting the paper feed cassette into the cassette accommodating portion, 
 wherein the temporary catching portion does not contact the flapper at the first position and contacts the flapper at the second position. 
 
     
     
       2. The image forming device according to  claim 1 , wherein the means for locking and the means for releasing are configured such that when the paper feed cassette is inserted into the cassette accommodating portion, a locked state of the flapper at the prescribed pressed-down position is released and the temporary catching portion temporarily catches the flapper within a vertical swinging range of the flapper, and when the paper feed cassette is completely inserted in the cassette accommodating portion, the flapper is released. 
     
     
       3. The image forming device according to  claim 2 , wherein the temporary catching portion temporarily catches the flapper when the means for locking is in contact with the means for releasing. 
     
     
       4. The image forming device according to  claim 3 , wherein the temporary catching portion temporarily catches the flapper at a substantially intermediate position within the vertical swinging range of the flapper. 
     
     
       5. The image forming device according to  claim 1 , wherein the means for locking includes:
 an acting member which is mounted on a chassis of the paper feed cassette in a manner capable of being swung around a horizontal pin, and 
 an elastic member which maintains the acting member at a standby position. 
 
     
     
       6. The image forming device according to  claim 5 , wherein the acting member includes an acting surface which functions to swing the acting member around the horizontal pin by the flapper acting against an elastic force of the elastic member when the flapper is pressed downward. 
     
     
       7. The image forming device according to  claim 6 , wherein the acting member includes a lock catching portion which maintains the flapper at the prescribed pressed-down position by an elastic restoration force of the elastic member when the flapper is pressed down to the prescribed pressed-down position. 
     
     
       8. The image forming device according to  claim 7 , wherein the acting member further includes the temporary catching portion which temporarily catches the flapper that is elevated after being unlocked. 
     
     
       9. The image forming device according to  claim 8 , wherein the means for releasing includes a protrusion formed on an inner wall of the cassette accommodating portion. 
     
     
       10. The image forming device according to  claim 9 , wherein when inserting the paper feed cassette into the cassette accommodating portion, the protrusion makes contact with the acting member and swings the acting member so as to release the locked state of the lock catching portion against an elastic force of the elastic member, the protrusion also catches the released flapper by the temporary catching portion, and accompanying a subsequent insertion movement, the protrusion releases the flapper caught by the temporary catching portion. 
     
     
       11. The image forming device according to  claim 10 , wherein the acting member includes a protruding side which makes contact with the protrusion when the paper feed cassette is inserted into the cassette accommodating portion. 
     
     
       12. The image forming device according to  claim 11 , wherein when the paper feed cassette is inserted in the cassette accommodating portion, the protrusion is located at an outer side than the protruding side. 
     
     
       13. An image forming device comprising:
 a paper feed cassette which accommodates a plurality of papers; 
 a cassette accommodating portion which removably accommodates the paper feed cassette; 
 a flapper which is arranged in the paper feed cassette and swings vertically; 
 an elastic urging member which is arranged in the paper feed cassette and urges the flapper upward; 
 a guide rib which is arranged on an inner surface of a front wall portion of the paper feed cassette; 
 means for locking the flapper at a prescribed pressed-down first position when the flapper is pressed down against an urging force of the elastic urging member; 
 means for releasing the means for locking when the paper feed cassette is inserted in the cassette accommodating portion; and 
 a temporary catching portion which is formed on the means for locking and stopping the flapper at a second position elevated higher than the first position when inserting the paper feed cassette into the cassette accommodating portion, 
 wherein the temporary catching portion does not contact the flapper at the first position and contacts the flapper at the second position. 
 
     
     
       14. The image forming device according to  claim 13 , comprising a plurality of guide ribs. 
     
     
       15. The image forming device according to  claim 14 , wherein the means for locking includes:
 an acting member which is mounted on a chassis of the paper feed cassette in a manner capable of being swung around a horizontal pin, and 
 an elastic member which maintains the acting member at a standby position. 
 
     
     
       16. The image forming device according to  claim 15 , wherein the elastic member is a torsion spring. 
     
     
       17. The image forming device according to  claim 16 , wherein the acting member includes an acting surface which functions to swing the acting member around the horizontal pin by the flapper acting against an elastic force of the elastic member when the flapper is pressed down. 
     
     
       18. The image forming device according to  claim 17 , wherein the acting member further includes a lock catching portion which maintains the flapper at a pressed-down position by an elastic restoration force of the elastic member when the flapper is pressed down to the prescribed position. 
     
     
       19. The image forming device according to  claim 18 , wherein the acting member further includes the temporary catching portion which temporarily catches the flapper that is elevating after being unlocked. 
     
     
       20. The image forming device according to  claim 19 , wherein the means for releasing includes a protrusion arranged on an inner wall of the cassette accommodating portion, and
 when inserting the paper feed cassette into the cassette accommodating portion, the protrusion makes contact with the acting member and swings the acting member so as to release the locked state of the lock catching portion against an elastic force elastic member, the protrusion also catches the released flapper by the temporary catching portion, and accompanying a subsequent insertion movement, the protrusion releases the flapper caught by the temporary catching portion.